Bridge marking receiver



Filed Aug. 6, 1947 BRIDGE MARKING RECEIVER R. M. M. OBERMAN ET AL June12, 1951 m ia-2212mm BY \w.

I Roelof M.

Patented June 12, 1951 BRIDGE MARKING RECEIVER M. Oberman and AntonieSnijders, The Hague, Netherlands Application August 6, 1947, Serial No.767,539 In the Netherlands August 22, 1944 Section 1, Public Law 690,August 8, 1946 Patent expires August 22, 1964 6 Claims. (01. 17888) Thepresent invention relates to a selecting system responsive to signals inthe form of different voltages.

The selecting device accordin to the invention comprises a series ofselector relays which are caused to assume a distinct and differentcombination of operative and non-operative positions in response toevery different signal voltage, as described in the copending patentapplication Serial No. 767,536 filed August 6, 1947, now Patent2,543,050, patented on Feb. 27, 1941.

The object of this invention is an improvement in which the finalcombination of operative and non-operative selector relays for anysignal is attained in a short time without the occurrence ofintermediate operation of any relay which in the final combination hasto be non-operative.

Another object of this invention is an improvement in which theoperatingdelays of the selector relays are independent of one another, the mutualrelationship of the relays being positively interlocking.

According to the invention the selecting system has a series of vacuumtubes, the number of which is equal to the number of the selector relayswhich have two opposing windings each, except the last having only onewinding.

The first winding of every relay is connected in the plate circuit of acorresponding tube. The second winding of each double-wound relay isconnected in the plate circuit of the next tube in the series, but isdisconnected when the next relay in the series operates.

The bias of said vacuum tube is derived from a potentiometer which hasas many taps as the number of tubes. The potentials of saidpotentiometer taps, with the exception of the tap connected to the lasttube, are controlled by the selector relays, except the first relay.

The invention will now be described in detail with reference to thedrawing which shows a wiring diagram of the selecting device.

In the drawing four selector relays A, B, C, D are shown. The firstthree relays have two windings each: A1, A2; B1, B2; C1, C2; but thelast relay D has only one winding D1. Windings A1, B1, C1 and D1 areconnected in the anode circuits of vacuum tubes BA, BB, BC and BD,respectively.

Windings A2, B2 and C2 are connected in the anode circuits of tubes BB,BC and BD, respectively. It follows that the tubes BB, BC and BD servetwo windings each, viz. A2 and B1, B2 and C1 and C2 and D1 respectively;BA serves only one winding A1. Relay contacts b3, 03, and d3 2 uncouplethe windings A2, B2 and C2, respectively, when the said contacts areoperated by their respective relays B, C, and D.

The uncoupling is performed by shunting in the drawing, but a difierentmethod of uncoupling would also be feasible.

Other relay contacts b1, b2; 01, 02; d1, d2 are connected to apotentiometer which comprises resistors W111 to W22. Operation of anyrelay makes all potentials on the control grids of lower order in theseries to shift by the same amount, this amount being differentlypredetermined for each relay. In the drawing all relays are shown intheir non-operative or normal position and in that position the controlgrid potentials are assumed to be -32, 34, --38 and -46 volts, re-

spectively.

The contacts b1/b2 cause a 4 volt shift of control grid BA, the contactsc1/c2 cause an 8 volt shift of grids BA and BB, and the contacts d1/d2cause a 16 volt shift of grids BA, BB and BC.

If the signal line has a potential of -30 volts, this being the normalor zero signal, all tubes and relays remain inoperative as shown in thedrawing. 7

Any other signal causes a distinct combination of tubes andcorresponding relays to become operative, according to the followingtable:

Table I Signal Tubes or relays stages number voltage (B) A (B) B (B) C(B) D 0 -30 1 1 32 1 2 34 2 3 -36 2 4 -38 2 5 -40 2 c 42 3 7 -44 3 8 -4c2 9 48 2 10 50 3 11 -52 3 12 54 a 13 56 3 14 58 4 15 -c0 4 The finalcondition of the tubes is the same as the final condition of thecorresponding relays, but there may be a few intermediate stages inwhich more tubes than relays are operative. Along these intermediatestages the condition of tubes and relays will be parallelled gradually,either by dropping tubes or by adding relays. Taking signal 6, (signalvoltage 42 volt) as an 2 example, the three stages of in Table II.

operation are given relay and the other winding being connected to thetube corresponding to the next succeeding Table II Signal Test voltageTubes Relay windings Relay armatures (BA) (B B) (B O) (B D) stage NO.V011: BA BB BC BD BA BB BO BD A B O D A] A: B; B: 01 02 D In the firststage the signal voltage of 42 volts on the four cathodes connected withone another renders tubes BA, BB and BC conductive, the control grids ofthese tubes being positive with respect to the cathodes. Tube BD with a46 volt grid remains non-conductive. Thus, relay windings A1, A2, B1, B2and C1 are energized, but only relay C is operated, because windings A1and A2, and likewise windings B1 and B2 mutually neutralize each other.The operation of relay C modifies the bias of the lower ordered controlgrids (BA and BB) with an 8 volt shift, thus starting the second stage.

The test voltages are now 40, -42, 38 and -46 volts respectively, andthe cathode voltage still being 42 v., no change in the operatingcombination of the tubes is eifected. The second winding B2 of relay Bis short-circuited, and this renders relay B to operate, as its firstwinding B1 is no longer counteracted by winding B2. The operation ofrelay B modifies the bias of the lower ordered tube BA with a 4 voltshift, and the third stage is started with the test voltages -44, i2, 38and 46 volts. The grid of tube BA is now 2 volts negative with respectto the cathode. This tube becomes non-conductive, and winding A1 istie-energized. Simultaneously, however, winding A2 is short-circuited byrelay contact b3; relay A remains inoperative. The shunting of relaywindings B2 and A2 is indicated by 0 in the above Table II.

It will be observed that in the first and second stage tube BA isoperative though its final condition is inoperative. It is a consequenceof the second winding of relay A1 that this relay is not operative inthe first and second stage, and this involves the advantage that theposition of each relay can be registered or used for transmission toother apparatus as soon as this relay operates. As it is not necessaryto wait for the completion of the combination, useful time can be saved,as well as the apparatus which would be required for the Waiting andsubsequent taking over.

By using pentodes as shown in the drawing the anode currents can be madepractically independent of the shunting of relay windings A2, B2, C2;but triodes can also be used.

While we have illustrated and described what we regard to be thepreferred embodiment of our invention, nevertheless it will beunderstood that such is merely exemplary and that numerous modificationsand rearrangements may be made therein without departing from theessence of the invention, we claim:

1. A selecting system responsive to different voltages comprising aseries of vacuum tubes having means for biasing them to be operative ondifferent voltage values, a series of relays having two windings actingin opposition, one of the windings of each relay being connected in theoutput circuit of a tube corresponding to the relay in the series, meansoperated by each relay to modify the bias of the tube corresponding tothe preceding relay and other means simultaneously operated to shunt theone difierential winding of the preceding relay which is connected inthe output circuit of the tube corresponding to the next relay.

2. A selecting system responsive to difierent voltages comprising aseries of vacuum tubes having means for biasing them to be operative ondifferent voltage values, a series of relays having a main winding andan auxiliary winding acting in opposition, said main Winding beingconnected in the output circuit of a tube corresponding to the relay andsaid auxiliary winding being connected to the tube corresponding to thenext succeeding relay in the series, means operated by each relay tomodify the bias of the tube corresponding to the preceding relay andother means simultaneously operated to shunt the auxiliary winding ofthe preceding relay.

3. A selecting system responsive to different voltages comprising aseries of vacuum tubes having means for biassing the same to beoperative on difierent voltage values, a series of relays having mainwindings connected in the respective output circuits of said vacuumtubes, each relay except the last having a counteracting auxiliarywinding connected to the next vacuum tube in the series when the nextrelay in series is not operated, said auxiliary winding beingdisconnected when the next relay in the series operates, and meansoperated by said relays for modifying the bias of the preceding ones ofsaid tubes to be operative on different signal voltages.

4. A selecting system responsive to different voltages comprising aseries of vacuum tubes having means for biasing the same to be operativeon different voltage values, an equal number of relays having mainwindings connected in the respecti've output circuits of said vacuumtubes, each relay except the last having an opposing auxiliary windingconnected to the next tube in the series, means operated by each relayexcept the first to shunt the auxiliary winding of the preceding relayin the series, and other means simultaneously operated for modifying thebias of the preceding ones of said vacuum tubes by the same amount so tobe operative on difierent signal voltages.

5. A selecting system responsive to different voltages, comprising aseries of vacuum tubes each having a cathode and a control grid, acommon connection of said cathodes to receive the signal voltage,potentiometer taps connected to said control grids, respectively, anequal number of relays having means to control the potentiometer tappotentials, each relay having a main winding and except the last of saidrelays an auxiliary winding, the output circuits of, said vacuum tubesfeeding said main windings of the respective corresponding relays andsaid opposing auxiliary windings of the respective preceding relays inthe series, means for shunting said auxiliary windings when the nextrelay in the series operates, and means simultaneously operated withsaid shunting means for modifying the bias of said vacuum tubes by thesame amount so as to be operative on different signal voltages, saidaccount being specifically predetermined for each relay.

6. A selecting system responsive to different signal voltages comprisinga series of vacuum tubes having a common cathode connection and controlgrids, different potentiometer taps connected to said control grids,respectively, an equal number of relays having main windings in therespective anode circuits and having opposing auxiliary windingsconnected to the next tubes, respectively, each relay except the firstin the REFERENCE S CITED The following references are of record in thefile of this patent:

UNITED STATES PATENTS Number Name Date 1,563,738 From Dec. 1, 19251,593,993 Sprague July 2'7, 1926 1,801,657 Buyko Apr. 21, 1931 2,008,563Sarbey July 16, 1935 2,295,534 Leathers Sept. 15, 1942

